I had to by a replacement beta today. My last one of 1yr+ started acting like he was depressed (despite my arguments with my husband who says fish dont get depressed)..I say that to be descriptive of his state. He was less active and stopped eating.

Anyhoo...I got a replacement (& of course cleaned sanitized & re-set up the tank)
My concern is this new fish, swims like he is having trouble. Kind of like Nemo from the movie only he doesn't have a small fin. He seems to favor one side. He has difficulty swimming the the top and then seems to fall back to the bottom sitting kind of upright but on his side (hope this makes sense.)

Any advice is greatly appreciated! Thanks in advance for reading & your time!